Groundwater and Drilling Services

Background Information
Zinwa is a Government of Zimbabwe parastatal established in 2000 after the amalgamation of the then Regional Water Authority and part of the Department of Water Development. The Groundwater Department of ZINWA has been involved with borehole drilling since the early 1920s and has thus gained vast amount of knowledge and skills in groundwater development in Zimbabwe.
The Groundwater Department of ZINWA provides technical advice on groundwater planning, development and management to the Ministry of Water Resources Development and Management and is therefore quite conversant with all the legal (regulatory and statutory) requirements associated with groundwater development in the country. This provides for the development and construction of high quality boreholes which meet the national standard on the Development, Maintenance and Management of Groundwater Resources currently under formulation

Services

Borehole Drilling Authorities
Before a borehole is drilled, authorization to drill the borehole has to be sought first from the appropriate Catchment Council. It is illegal to drill a borehole without the authorization. ZINWA Groundwater Department can easily facilitate authorisations to drill boreholes only for boreholes it will have been hired to drill.

Groundwater Abstraction Permits
An abstraction permit is required before abstracting groundwater. It is illegal to abstract water without a valid permit obtainable from the appropriate Catchment Council. ZINWA Groundwater Department is very conversant with all types of the permits needed for the various situations and the registration required. ZINWA Groundwater Department would secure abstraction permits for its clients without the valued client going through the various processes.

Research and Development
ZINWA Groundwater Department is currently spearheading research in the manufacture of high quality borehole casing from PVC locally with the aim of:
making the borehole cost affordable ensuring that the quality of your potable water is not affected by rusting which could result if steel casing were used.

Borehole Drilling
It is illegal to drill a borehole in Zimbabwe without an Authority to Drill a Borehole. It is also illegal to abstract water without a valid permit. ZINWA Groundwater Department can drill boreholes to depths in excess of 300m and diameters up to 500mm. The Department has skilled and experienced manpower which has been trained by veterans in the groundwater development business and are capable of undertaking any assignment with very little managerial supervision. A field Drilling Superintendent and a Drilling Supervisor are mandated with daily field operations. Highly qualified and experienced staff provides technical and management backstopping. Boreholes are drilled to obtain water for various purposes:

Domestic Water
This has to be potable water and ZINWA Groundwater Department guarantees this. Groundwater generally provides good quality water suitable for domestic purposes. ZINWA Groundwater Department has been involved in groundwater development since the early 1920s as a government arm and now as ZINWA Groundwater Department since 2001 to date Borehole depths range from 40-100m but average 45-50m. Note: According to the Zimbabwe Standard for Development, Maintenance and Management of Groundwater Resources, boreholes have to be deeper than 30m. Borehole diameters range from 150mm-200mm. The most common diameter for domestic boreholes is 150mm.

Agricultural Water
Boreholes for agricultural use need to produce adequate water to meet requirements. This is ZINWA Groundwater Department’s piece of cake to give you quality water for quality crops and for healthy cash returns through:

Drilling deep boreholes to suit all your irrigation requirements

Borehole depths generally range from 60-100m

Borehole diameters range from 150-300mm. The most common diameter for irrigation borehole is 200mm.

Industrial Water
ZINWA Groundwater Department endears to providing you with a peace of mind for your company/organisation growth through uninterrupted quality groundwater supply.

Borehole depths range from 50-60m

Borehole diameters range from 150-200mm with 200mm being most common diameter for industrial boreholes

Institutional Water
ZINWA Groundwater Department, through its predecessor organizations, had made it its business to ensure sustainable water supply to schools, hospitals, growth points, government institutions, etc. We recommit ourselves to ensuring high quality services for the sector.

Borehole Construction
Quality boreholes are born from the way they are constructed. All boreholes are professionally constructed. High quality mild steel or PVC is used as borehole lining.

Casing
Provides structural support against caving and seals off undesirable groundwater such as saline (salty) water.

Screens
Screens provide structural support against caving and prevent entry of sand and allows maximum amount of water to enter the borehole so as to ensure high groundwater abstraction volumes.

Gravel Pack
Did you know that it is only ZINWA Groundwater Department that installs gravel pack in the boreholes it drills and constructs? Gravel pack is installed between the screens and hole walls and is very important in:

Stabilising the aquifer, preventing collapse of the formation which

would otherwise lead to low abstraction volumes,

Minimising sand pumping which would otherwise damage the pump,

Permitting the use of a large screen slot with maximum open area which allows high abstraction volumes, and

Drinking Water Quality

Providing an annular zone of high permeability, which increases the effective radius and yield of the well.

Other Services

Geophysical Investigations, and

Supply and installation of handpumps.

There you have it!! Gravel packing a prerequisite for a good borehole and who can best do it – ZINWA Groundwater Department

Water Quality Analysis
Potability of water is determined by its quality. Poor quality water poses a serious risk to humans, crops, livestock and the environment. ZINWA Groundwater Department has the equipment to analyse the quality of water both on site (at the borehole) and at its laboratory. We have developed working synergies with other reputable laboratories for quality control of our services.

Hydrogeological Consultancy

Industrial Effluent Quality

ZINWA Groundwater Department has experienced professionals who know the hydro-geological setting of Zimbabwe in and out. The department offers hydro-geological consultancy services in:

Pumping test design, data acquisition and interpretation,

Groundwater occurrence,

Hydro-chemistry,

Isotope hydrology, and

Hydro-geological monitoring networks

and many more.

Machinery
The Department has borehole drilling machinery and equipment capable of drilling various sizes of borehole diameters (up to 500mm) and to depths exceeding 300m in unconsolidated geological formations such as in Gokwe South district. The Department has relatively new high pressure compressors (25bar) which will aid in the expeditious drilling of boreholes. Equipment for borehole drilling range from down the hole hammer (DTH) for drilling in hard rock formations to mud rotary equipment meant for drilling in unconsolidated and collapsible formations.
Referrals
The Department has, over the years, drilled thousands of boreholes for domestic water supply through the rural water supply and sanitation programme, Government Institutions, private organizations and individuals and for agricultural purposes, mainly for irrigation.